Vital Signs is a monthly program bringing viewers health stories from around the world.

Arusha, Tanzania (CNN) -- "They are happy because [there's] no disease for them and no children get sick," explains 52-year-old Jacob Mmali referring to the two elders from his village who stand beside him. The three Maasai men are from the indigenous tribe of the same name and reside in the small village of Enguiki, in the region of Arusha in North-Eastern Tanzania. Diseases such as measles once plagued their community. But not anymore.

As I began encroaching upon their village the men were quick to walk over and inquire about this new face walking on their land. I could after all bring disease.

Surrounding the men is a vast savannah. Vegetation is scarce, dirt roads lead out into the distance and the Great Rift Valley lurks close by. The sparse resources found here are why men from this tribe typically migrate from region to region with their cattle, in search of pastures to graze on. But unlike many who live in this remote part of the country, the men have one very useful facility just meters away -- a health dispensary. The Monduli Juu health dispensary.

Maasai elders in their village of Enguiki, Tanzania.

Meera Senthilingam/CNN

Dispensaries are the most basic form of health facility in countries such as Tanzania. They're a first point of contact when illness occurs and anything serious is referred on. But despite their isolated location, they house life-saving vaccines. Not one or two, but the full range of 11 routine vaccinations recommended for use in the population, ensuring locals are protected from disease as they roam with their cattle. Numerous children play nearby in the village, all of whom will have received their vaccines.

Previously measles killed a lot of children in the Maasai and with the introduction of vaccines it made a big difference Dr. Zavery Benela, Monduli District Medical Officer

Unlike Mmali, the elders, aged 65 and 68 years of age, do not speak English and as I inquire about their vaccination status they instead lift the red cloth draping over their arm to show me their scars acting as evidence of their immunizations. The two men are unsure how many children they have produced from the six wives they have between them but one thing they are sure of is that their children need to be fit, healthy, and productive.

Mmali doesn't wear the traditional cloth and jewels the Maasai are famous for, but is instead dressed in a football shirt and woolly hat depicting the logos of Arsenal and other well-known football clubs. He is dressed to farm his land which the morning's rain has prevented him from attending to. Mmali suffered measles as a child and recalls his parents taking him to hospital for treatment. As a result he made sure his five children are protected. "Vaccines are important because they protect people to get no measles around the village," he says.

Simple and effective -- Babies are weighed before receiving vaccines.

Tom Maguire/RESULTSUK

The men have not seen any cases of measles in recent years and talk only of rare diseases such as trachoma, an ancient infection affecting the eyes, for which there is no vaccine.

Getting mobile to take down measles

Numbers of measles cases in Tanzania reached almost 15,000 in 2000 and outbreaks of infection continued thereafter with over 1600 reported cases of the disease in 2011 and again in 2012.

Before, we had wards specifically for measles. We don't' have them anymoreAziz Sheshe, Regional Immunization Vaccine Officer, Arusha

"Previously measles killed a lot of children in the Maasai and with the introduction of vaccines it made a big difference," explains Dr. Zavery Benela, Medical Officer for the district of Monduli where Enguiki, and many other villages, are located. The districts all fit into the larger region of Arusha which is predominantly populated by Maasai tribes whose nomadic lifestyles make them hard to reach. Lack of birth registration and certificates by some can also make their ages hard to define. This hasn't stopped health services from rising to the challenge.

"Initially we had the problem of those who do not complete their schedule," says Benela. Protection against measles requires two doses of the measles vaccine and routine vaccinations such as DPT (against diphtheria, pertussis and tetanus) require three doses. Rather than wait for people to return, Benela and teams across the country choose instead to go to them, using mobile clinics. A cold box is packed full of ice and vials and accompanies them in their four-wheel drive as they venture across the savannah to reach the unreachable. "Once a month,, a team of 5 [health workers] with a driver are carried with a mobile team". The mobile services in the district of Monduli have 41 posts to reach the 159,929 people that live there according to the 2010 census, and efforts have paid off.

A baby receives a vaccine against rotavirus.

Tom Maguire/RESULTSUK

"For 2013, the average vaccination coverage for most of the vaccines in our district was 98 percent," Benela states proudly. Diseases such as measles require at least 83 to 94 percent of the population to be vaccinated in order to prevent new infections from spreading, known as herd immunity. The district of Monduli has seen no deaths from measles in 2014.

Fall in Nomadic behaviour

Some success however comes down to the changing lifestyles of the Maasai who have decreased their nomadic ways in recent years to become more synchronised with the rest of the countries cultures and communities. The change brings a smile to the faces of those trying to improve their health.

"That has helped a lot, and actually even school attendance has improved because their movement is not as it used to be," says Benela. "The Maasai used to be nomadic for most of the dry season but now only the head of the household will move with the cattle looking for the grazing areas, so now most have some permanent houses."

The national immunization coverage for Tanzania in 2012 was 92 percent, a drastic improvement from the 79 percent covered in 2000. Given that 77 percent of the population live rurally, the accomplishment is somewhat more remarkable. Some of the country's poorest and most remote regions continue not to reach this threshold but they're learning from successes such as Monduli, and the overall region of Arusha where it lies.

"Before, we had wards specifically for measles. We don't' have them anymore," says Aziz Sheshe, the Regional Immunization Vaccine Officer for Arusha. "So we know the vaccinations are working".

Maasai community member Jacob Mmali standing by his local health dispensary.

Meera Senthilingam/CNN

Sheshe has fought to ensure every child is protected against disease, particularly the Maasai who dominate his region. "Today they're here and tomorrow you don't know where they will be so it's very very difficult," he says. "Now we are talking with their [village] leaders and know they have shifted to certain areas so it's easier to locate them".

Cold Chain Conundram

Word of Ebola has reached these remote communities

The journeys to reach and vaccinate these remote communities can be treacherous. The temperature-sensitive vials of vaccines have an arduous journey to cover the 945,000 square kilometres of land Tanzania occupies. To remain intact and functional, the vials must be kept cool at two to eight degrees Celsius and vaccines such as polio and measles require being frozen down to minus 25 degrees at certain stages of their journey.

Four times a year, millions of vaccines arrive at the country's central vaccine store in Dar es Salaam where 30 ft cold rooms house them at these cool temperatures. On the hot, intensely humid, November day I visited these stores, over 3.5 million vaccines were chilled and ready to go.

Where vaccine delivery is concerned, the United Republic of Tanzania is divided into 26 regions which reach out across the Indian Ocean to include the island of Zanzibar. Refrigerated trucks disperse hundreds of thousands of vaccines to each inland region, taking up to two days to reach them. Once there, the treasured cold box, is solely responsible for the final distribution of vaccines first to a district hospital and then the eventual trickle down to dispensaries such as Monduli Juu where Mmali and his elders stand talking to me. My journey from Dar es Salaam took a similar amount of time, but without a cold box or ice packs my appearance was somewhat less preserved.

In each dispensary, large blue boxes are the final homes for hundreds of vials now kept cool by generators. At Monduli Juu, tens of mothers visit each day with their newborn children. Further afield, the mobile clinics see 150 to 250 children flock to them each month for this biological protection. The supply chain is no easy feat.

A push from Ebola

Communication has been key in getting people on board with the benefits of immunization. Despite the outbreak being centered over 4500 miles away, word of Ebola has reached these remote communities and provided a surprising boost to immunization efforts. Fear of the disease increased the uptake of vaccines in a recent measles and rubella campaign which took place nationally in October 2014.

When we go to the field we see different thingsAziz Sheshe, Regional Immunization Vaccine Officer, Arusha

"People thought that Rubella was Ebola," says Sheshe almost laughing in shock at the situation vaccinators faced when out on the ground. Adults and children alike came to sites where vaccinations were taking place expecting to receive a vaccine against Ebola. Their misuderstandings were clarified on the spot but inevitably resulted in high coverage levels. ""People [were] saying 'this is Ebola vaccine, we need it we need it', even people who are not eligible for Rubella". The rubella vaccine was only eligible in children aged 9 months to 15 years of age as this age range encompasses 50 percent of the country's population. Tanzania has a young population in which the median age is 17 years.

The Measles and Rubella campaign came as Tanzania saw sudden increases in the numbers of people contracting this rash-causing virus which can result in congenital abnormalities if contracted during pregnancy. There were 116 cases of rubella in 2013, after just 18 cases in 2011. "Rubella is now coming, we don't know when it started but we know it's there and not all the communities have protection," says Sheshe. Thankfully, belief in immunization has spread.

Ebola co-discoverer on how vaccine works

When it comes to disease, the Maasai have traditionally resorted to natural remedies from native plants in their surroundings, such as the Sodom apple. Still standing by his village, Mmali eagerly plucks a few samples of the plant to explain its use against malaria among his peers. But he readily acknowledges that western medicine now plays a big part in the community's health.

The Monduli Juu dispensary vaccinates on average 10-12 children each day, with people walking five to six kilometres to get there. The mountainous terrain means this seemingly short distance can take hours to complete. Ten children were due to come in that morning but the heavy rain which fell earlier has kept them away. One anxious mother braved the rain to bring her feverish child to the facility for further assistance.

Children playing by the Monduli Juu dispensary.

Meera Senthilingam/CNN

Not over yet

Ninety-five thousand children under 5 years of age continue to die from preventable and treatable conditions in Tanzania each year. Leading causes of death include pneumonia and diarrhoea for which two vaccines, pneumococcal and rotavirus, were introduced nationally in 2013. With the increasing popularity of immunization among the Maasai, and Tanzanian population as a whole, the key challenge health teams now face is one of supply, not demand. More children are requesting vaccinations than local stocks are equipped for, particularly in the most remote regions where accurate headcounts are not possible. The use of 2010 census data does not represent the population in the field today.

Ancient Maasai culture in the modern world

"When we go to the field we see different things, there are many children on the ground," describes Sheshe about his region of Arusha. "For our recent (measles and rubella) campaign we expected 680,000 and we saw more than 700,000."

Eating like a Maasai

New technologies are being developed and coordinated by the vaccine alliance GAVI, WHO and global health NGO PATH, to accurately record population sizes in real-time. This will ensure vaccinators know what to expect as they greet the crowds of children that surround their mobile clinics on arrival. "We'll be able to know how many children are there at every village and right now we are not sure," says Sheshe. The use of barcodes to track vaccines as they traverse the country is also being trialled, for accurate stock records at even the most remote of facilities. "You need to see the stock level at every facility and right now it's very difficult, Arusha has more than 200 health facilities. You can't ring up every single one," explains Sheshe.

Tanzania remains a country setting examples of how to improve the health of a majority rural nation. But these final creases need ironing out to further boost levels of immunization to the desired optimum of 95 percent of the population. The teams working on this feel the pressure. "Now, if you talk about vaccines...it's only the health system which will fail them, not the community".

Indeed Mmali and his community in Enguiki will not fail their children and instead fight to keep them strong and fit. For now, village life continues. The young ones continue to play and climb onto swings in the small playground nearby, the elders have decided I pose no risk and use their sticks to wander back into their village, and Mmali bids farewell as he goes to tend to his land. "Vaccines are for a long time," he concludes. When it comes to their health, this community are here to stay.